本文以分子動力學模擬多元合金奈米團簇從高溫熔融狀態冷卻至室溫之結構變化情形，所採用勢能參數為緊束法(Tight-Bindind Method)之半經驗勢能函數，並以RDF、 Wendt–Abraham parameter 及 Pair Analysis方法討論製程參數包含合金的組成成分、添加元素及淬火速率對合金團簇結構的影響。由合金組成成分的結果可知，由於第三元素成份之增加，使面心立方結構特徵(1421)隨之遞減，二十面體結構特徵(1431、1551、1541)有遞增之現象，但是在體心立方結構特徵方面因為金屬間化合物的產生使(CuNi)0.78Al0.22會有增加之現象。由合金添加元素的結果可知，因為鋁大於鎳之原子半徑14.4%相較於銠(8%)大上許多，這表示添加鋁元素造成原晶格破程度比銠元素能力強，所以使合金團簇具有較大之非晶質形成能力。由合金淬火速率的結果可知，因為淬火速率的不同造成合金團簇有晶質相與非晶質相的產生，並利用Wendt–Abraham parameter可以明確找出各多元合金團簇的轉換溫度。最後提出分子動力學模擬之瓶頸及改進方法，作為今後努力的方向。

　The present study investigates the structural behavior of multi-elements alloy nanocluster in a defined temperature range between high and room temperature with the principles of molecular dynamics simulation. The applied potential parameter is the semi-empirical potential parameter of the tight-binding method. The fabrication parameter is analyzed by RDF, Wendt-Abraham parameter and pair analysis, including the effects of composition of alloy, additive elements, and quenching rate on the structure behavior of alloy nanocluster. The structural characteristic of the alloy nanocluster is directly influenced by the concentration of third additive. The increase in the third additive reduces its characteristics of element face centered cubic (FCC) (1421), but increases its characteristics of both icosahedron (1435, 1551, 1541) and body centered cubic (BCC). The increasing characteristic of BCC is the result of the formation of an intermetallic compound (CuNi)0.78Al0.22. Since the atomic radius of aluminum is larger than that of rhodium, the addition of aluminum led to a higher degree of lattice disruption than rhodium, and thereby renders the alloy nanocluster a higher degree of amorphous alloy formation (14.4 vs. 8%). The differences in the quenching rate of the alloys render the formation of amorphous and crystalline phases. The Wendt-Abraham parameter is then employed to determine the transition temperature of the alloy nanocluster. The limitation of the molecular dynamic simulation is also proposed in this study, and its improvement is an ongoing objective.

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